Dolphins are highly intelligent marine mammals and can be found worldwide, usually in shallow seas. They are carnivores, mostly eating fish, squid and crustaceans. Bottlenose Dolphins are grey in colour, and have a distinctive dorsal fin which appears when they come up to breath at the surface. They are very social animals, travelling in groups from 5 individuals up to several hundred. Dolphins usually only give birth to one calf, which will still stay with its mother until it is 3 to 8 years old. Learn all about dolphins in this video!